Bifunctional core-shell nAl@MOF energetic particles with enhanced ignition and combustion performance

Abstract

With the continuous development of advanced fuel and engine technology, the boundary between liquid and solid fuel is more and more blurred, so the development of new solid-liquid two-phase fuels has become a major opportunity and challenge. Herein, two kinds of nAl@MOF energetic particles (nAl@Zn-MOF and nAl@Co-MOF) were fabricated by an in-situ electrostatic self-assembly method. The thermal property, ignition and combustion performances of nAl@MOF are characterized by TG-DSC, CO2 laser ignition and constant-volume combustion experiments. The results show that the initial exothermic temperature of nAl@Zn-MOF and nAl@Co-MOF are reduced by about 60 and 110 °C, respectively, compared with nAl (579.6 °C). Moreover, nAl@MOF has a lower ignition delay time, higher peak pressure, and faster pressurization rate than nAl, especially nAl@Zn-MOF-1 and nAl@Co-MOF-1. The combustion process of nAl@MOF is proposed, which can be obviously enhanced by regulating the interfacial reaction and the generation of microexplosions. In the ignition experiment of nanofluid fuel, nAl@MOF energetic particles exhibit the bifunction characteristics, which can simultaneously improve the ignition and combustion performances of solid-phase nAl particles and liquid-phase hydrocarbon fuel. This work provides a new strategy for advanced aerospace fuel by introducing MOF shells to construct bifunctional energetic particles with enhanced ignition and combustion properties.